The present invention provides an apparatus and method for characterizing tire pressure on the four tires of a conventional passenger automobile. The method uses an apparatus disposed on a key fob. The key fob includes a tire valve stem interface that is capable of taking manual measurements of tire pressure. The fob further includes a pressure transducer that translates tire pressure into electronic form where it can be displayed on an LCD screen and transmitted by RF to an automobile computer. The automobile computer further includes a program that provides for the measurement of tire pressure in a sequential method thereby assuring that the tires are at placarded pressure or more. The method includes steps of using the key fob to measure the tire pressure and transmitting the tire pressure to the computer for processing.